I agree that the edge of ruler needs to be exactly lined up with the fold of the fabric. Keep that edge toward you. If it's 22 inches away, you can't get as clear a view. Do not use the selvages as your straight edge. I assume you are using a ruler at least 6 inches wide. If not, you can butt another ruler up to it check for exact straightness. I always straighten the fabric first, whatever it takes and keep an eye out for any loss of exactly straight after a few cuts.